METALLOGENY OF THE BEATON — CAMBORNE MINING CAMP LARDEAU DISTRICT (082K 12 & 13)

By B.N. Church and L.D. Jones, B.C. Geological Survey

KEYWORDS: Beaton, Camborne, Trout Lake, wagon road was built to Trout Lake from veins, gold silver, lead, zinc, molybdenum, tung- Thompson’s Landing (renamed ‘Beaton’ in sten, Lardeau Group, Kootenay Arc. 1903) on the Northeast Arm of Upper Arrow Lake. In the succeeding eight years many gold claims were staked and developed. Four or five INTRODUCTION stamp mills were erected to process the quartz- The Beaton area (NTS 082K12,13) compris- rich vein ore and the town of Camborne, found- es several former mines and dozens of mining ed in 1901, grew rapidly. In 1902 the railway prospects scattered across 200 square kilometres was extended to Gerrard at the south end of in the Lardeau district, West Kootenay region of Trout Lake and steamer service began on the southeastern British Columbia. The area is cen- Arrow Lakes. Activity peaked in 1904 but the tred just north of the settlement of Trout Lake, operations at Camborne soon proved unprof- 60 kilometres southeast of Revelstoke and 140 itable due to a combination of poor manage- kilometres north of Nelson in the heart of ment, low ore grades and metallurgical prob- Selkirk Mountains lems. By far the greatest proportion of the ore Prospecting for metalliferous deposits in the that was shipped was hand sorted to produce a Lardeau district began prior to 1890. A crew led silver-lead product. Large quantities of ore con- by Peter Walker, following up on a rumor of new taining sphalerite, accompanied by appreciable mineral discoveries, travelled down the amounts of silver and gold, were left on mine Columbia River from Revelstoke to Upper dumps because of a penalty imposed for zinc by Arrow Lake and overland to Trout Lake. Mining the smelters. By 1908 there was a decline in activity started in the late 1890’s after more activity and by 1920 Camborne was practically a prospectors overflowed from the Slocan and ghost town. In 1927 the area revived somewhat Kootenay Lakes area. By 1899 mineral claims when the Multiplex Mining, Milling and Power were located near Beaton on the Northeast Arm Co. renewed work on their properties along Pool of Upper Arrow Lake and along the Creek. During the years 1935 to 1941 activity Incomappleux (Fish) River. consisted mainly of mill cleanup and salvage The history of the Lardeau district revolves projects. Then there was a resurgence of explo- about three mining camps - the Camborne camp ration and development in the 1950’s. The on the Incomappleux River east of Beaton, the Spider mine was brought into production in Ferguson camp east of Trout Lake and the Poplar 1952 and continued operations until 1958. Creek camp south of Trout Lake. This paper dis- During this period deposits other than just cusses the mines and mineral occurrences in the silver and lead were explored in the district. For Beaton map area including the Camborne camp. example in 1942 the Lucky Boy mine on Trout In the early years gold and silver-lead ores Mountain produced 20 tonnes of scheelite (cal- from the the Camborne camp attracted the most cium tungstate) in addition to the previous pro- attention. Claims on Sable Creek, Lexington duction of important amounts of silver and lead. Mountain and at the head of Mohawk Creek, Although molybdenite was first reported on the were responsible for much of the interest. In July property in 1917, it was not until 1969 and 1975- 1899, good gold values were obtained from a 1982 that further exploration led to the delin- quartz vein on the Eva claim on Lexington eation of major molybdenite reserves at what is Mountain and a prospecting rush ensued. A now known as the Trout Lake deposit.

Geological Fieldwork 1998, Paper 1999-1 193 overlain by phyllitic schists, quartzites and lenticular greenstone formations. The Milford and Kaslo groups are metamorphosed oceanic assemblages that include phyllites, thinly bed- ded calc-silicate metasedimentary rocks, chert beds, basic volcanic rocks and serpentinites (Fyles, 1967). The Mesozoic formations constitute the Quesnel terrane that lies along the western side and within the curvature of the Kootenay Arc. The Kaslo and Rossland volcanics (Hoy and Revelstoke Dunne, 1997) and the Slocan argillite, slate and limestones are important units in this terrane and contain significant silver-lead-zinc deposits typ- Vancouver ical of the Lardeau and Slocan mining districts. Beaton Area Many batholiths and arrays of small stocks Figure 1. Location map, Beaton-Camborne mining interrupt the continuity of the older deformed camp. stratigraphic succession throughout the Intermittent exploration activity continues in Kootenay Arc. The Kuskanax and Nelson the area driven by changing market conditions batholiths are the largest intrusions. They are for precious and base metals, new geophysical predominantly granite and granodiorite in com- and geochemical methods and new geological position although diorite, monzonite and syenite interpretations. are locally important phases. The age of these rocks is generally considered to be middle or late GEOLOGICAL SETTING Jurassic age (Armstrong, 1988; Sevigny and Parrish, 1993). The geology of the Beaton area (NTS The Nelson batholith and many of the relat- 082K/12,13) comprises diverse lithological ele- ed granitic stocks have local zones of intense ments belonging to several tectonic terranes deformation around their margins. Regional (Figure 2). On a regional scale, the Beaton- structures are deflected into near parallelism Camborne mining camp is within the Kootenay along the margins of these intrusions. It may be Arc which lies between the Windermere-Purcell that antecedent structures controlled the anticlinorium on the east and the Monashee and emplacement of the granitic masses. Shuswap metamorphic complexes to the west Cretaceous and Tertiary intrusions are com- and northwest (Reesor and Moore, 1971; mon in the northern part of the arc and to the Reesor, 1973). east. These include medium-size plutons and The Kootenay Arc is a 400-kilometre-long small stocks of fresh granite, monzonite and curving belt of early Paleozoic to Mesozoic sed- syenite such as the Battle Range, Fry Creek plu- imentary, volcanic and metamorphic rocks. It tons and the Mount Toby and Glacier Creek trends northeast across Washington state into stocks east of Kootenay Lake (Smith and British Columbia, then north along Kootenay Gehrels, 1992). Lake and northwest into the Arrow Lake and Revelstoke area. Lardeau Group Along Kootenay Lake the arc succession comprises the Hamill, Badshot, Lardeau, The Lardeau Group, as defined by Fyles Milford, Kaslo, Slocan and Rossland groups. and Eastwood (1962) in the Ferguson area, The Hamill, Badshot and Lardeau constitute the consists of 6 conformable Lower Paleozoic early Paleozoic pericratonic Kootenay terrane; units named the Index, Triune, Ajax, Sharon the Milford and Kaslo belong to the accreted late Creek, Jowett and Broadview formations. This Paleozoic (and early Mesozoic) Slide Mountain succession was believed to be an upright terrane. The Hamill is mostly quartzite; the stratigraphic sequence having the Index Lardeau comprises a lower calcareous section Formation at the base and the Broadview

194 British Columbia Geological Survey Branch 51O 00'

1 00' 118 1 1 45' 117

1

7 O O O

3

0

'

50O 45'

N

048

kilometres 50O 30' Figure 2. Geology of the Beaton area (modified after Read, 1976, and Read and Brown, 1981). See legend next page.

Geological Fieldwork 1998, Paper 1999-1 195 Figure 2. Legend

Formation at the top. However, the highly formation is highly variable, black and grey folded condition of the beds, the lack of facing phyllite facies predominate near the base at the indicators and the presence of faulted contacts contact with the Badshot Formation, while hindered verification of this interpretation green phyllite predominates in the upper part (Smith and Gehrels, 1992). of the unit (Fyles and Eastwood, 1962). The The Index Formation is the most extensive Index Formation is overlain by a conformable unit in the Lardeau Group. The Index assemblage of black siliceous argillite, grey Formation comprises a thick sequence of grey, quartzite and black siliceous argillite known green and black phyllite, limestone and thick respectively as the Triune, Ajax and Sharon calcareous phyllite, tuff, tuffaceous Creek formations. The Jowett Formation is a greywacke, pillow basalt and rare quartzite and greenstone unit intercalated with the quartzo-feldspathic gritty sandstone. In vicini- Broadview Formation. The Jowett consists of ty of McDougal Creek, along the volcanic breccias and pillow lavas (Photo 1) Incomappleux River, the formation consists of altered locally to chlorite schist. The predomi- crystalline limestones and interbanded slates nant lithology of the Broadview Formation is and phyllites (Figure 2). Many of the limestone grey green, gritty quartz wacke or subarkosic bands are highly carbonaceous - some of them wacke with grey to black or green slate or containing a considerable amount of graphite, phyllite interbeds. Two important bands of while other bands contain sufficient chlorite to quartzite, assigned to the Broadview give a green colour to the rock. Although the Formation, cross the valley of the

196 British Columbia Geological Survey Branch have established a somewhat older age range for these rocks (Smith and Gehrels, 1992). The Nelson batholith underlies much of the western part of the Kootenay district where it is a complex of intrusives rocks differing in struc- ture, texture and composition. The Nelson batholith is the principal rock type within the Slocan City camp and in this area it is subdivid- ed into three phases (Cairnes, 1934) - granitic porphyry, crushed porphyry, and massive equigranular granite and granodiorite. The granitic porphyry is the predominant phase and hosts most of the ore deposits. Exposed surfaces of the rock are light grey with a flesh-colour hue due to weathering of the feldspar. It is character- istically coarse-grained and distinguished by rec- tangular phenocrysts (megacrysts) of potassium feldspar, commonly several centimetres long and comprising up to 50 per cent of the rock. These megacrysts are simple or Carlsbad twins of perthitic orthoclase replaced locally by micro- cline. The megacrysts are set in a coarse grained groundmass comprising subhedral plagioclase (An30-50), anhedral quartz, irregular clots of amphibole and biotite, interstitial microcline, and Photo 1. Deformed pillow lava sequence, Jowett minor amounts of apatite, sphene, magnetite and Formation, Lardeau Group. sulphides. Thin sections and chemical analyses indicate that the rock is a silica-poor granite verg- Incomappleux River – one a short distance ing to monzonite composition, having roughly below the mouth of Menhinick Creek and the equal amounts of alkali feldspar and plagioclase other below the mouth of Sable Creek. This and an alkali/lime index greater than 1. quartzite is an exceedingly hard, compact, dark The various phases of the Kuskanax blue rock invaded extensively by numerous batholith are leucocratic and as such are readily quartz stringers. Size grading is occasionally distinguished from the neighbouring Nelson seen, however, a consistent sense of facing batholith. The Kuskanax rocks are, in general, could not be ascertained across the stratigra- medium to fine grained types which in places phy because of the intense deformation of along the border of the intrusion show a well these rocks. defined porphyritic texture. Syenite is well developed along the border of the batholith where it forms stock-like apophyses. Elsewhere Kuskanax and Nelson Intrusions the batholith is chiefly granite. The Kuskanax batholith, named by Cairnes The Kuskanax rocks are mostly light (1929), borders the southwest side of the coloured, although the syenite generally weath- Lardeau area from near the north end of the ers brown and thus distinguished from the gran- Kootenay Lake to the Northeast arm of Upper ite. The granite is also generally finer grained Arrow Lake. The rocks of the batholith are typi- than the syenite. In thin section all phases show cally medium to fine grained, light coloured an abundance of both orthoclase and micro- granite. Dikes and sills from the batholith vary cline. Plagioclase occurs chiefly as perthitic from granite through syenite to granodiorite and intergrowths; the abundance of perthitic inter- diorite composition. Cairnes believed the growths being a distinctive feature of these Kuskanax batholith to be younger than the rocks. The amount of quartz varies from very Nelson batholith, however, more recent studies little in the syenite to conspicuous proportions

Geological Fieldwork 1998, Paper 1999-1 197 in the granites. The quartz exhibits little evi- Table 1. Chemical analyses of Galena Bay dence of strain or fracturing. Ferromagnesian granitic rocks. minerals are few and occur as minute blackish 12 specks throughout the rock. The chief mafic SiO 71.90 69.62 mineral is dark green to bluish green amphibole 2 which is usually partly altered. Accessory min- TiO2 0.18 0.27 erals include sphene, apatite, magnetite, yellow Al2O3 15.00 14.84 garnet and occasional sulphide grains. Fe2O3 1.41 1.77 Secondary minerals are mainly kaolin, chlorite FeO - 1.08 and calcite. MnO - 0.03 A peculiar feature of the Kuskanax batholith MgO 0.37 0.52 is the paucity of mineralization associated with CaO 2.23 2.99 this body. This is in direct contrast to the Nelson Na2O 4.28 3.55 batholith and, in particular, the Nelson granite K2O 3.18 3.22 whose relations to ore mineralization in the BaO 0.18 0.14 Slocan area have been previously indicated LOI 0.66 0.98

(Church, 1998). Except for occasional grains of P2O5 0.05 0.12 pyrite, no significant mineralization was noted Sum (%) 99.44 99.22 in the principal phases of the Kuskanax batholith. Normative Composition Qz 26.9 28.2 Or 19.1 19.6 Galena Bay Stock Ab 39.0 32.8 The Galena Bay stock outcrops at the head of An 11.2 15.3 Upper Arrow Lake intruding the north end of the Wo - - Kuskanax batholith along the eastern margin of En 1.0 1.5 Fs 2.0 0.1 the Monashee complex. The stock was originally Mt - 1.9 considered to be Kuskanax (Cairnes, 1929; Ll 0.3 0.4 Walker et al., 1929), however, K/Ar dating on He - - biotite and muscovite yielded 68 and 92 ± 8 Ma Cr 0.5 0.2 dates, respectively, (Leech et al., 1963) which is significantly younger than Kuskanax but similar This table is based on fused disc x-ray fluorescence for the major oxides in rock pow ders and normative mineral to the Trout Lake intrusion, dated 76 Ma by K/Ar calculations (molecular). Sample No. 1 is from the Galena analysis of biotite (Boyle and Leitch, 1983). Bay granitic stock located midw ay betw een Galena Bay The Galena Bay stock is a light coloured and the junction of Highw ay 23 and 31. Sample No. 2 is two mica granite similar to the muscovite - typical of the granitic rocks hosting molybdenite-bearing biotite bearing phase of the Battle Range plu- veins at the Trout Lake Mine. ton in the headwater area of the Incomappleux River. In thin section these terized in thin section by oscillatory zoned, rec- rocks are hypidiomorphic granular and con- tangular plagioclase and altered potassium tain abundant quartz, plagioclase and signifi- feldspar laths (to 3 mm in diameter) set in a cant amounts orthoclase and microcline. quartz-rich fine grained matrix with peppery Biotite is an accessory mineral and occurs biotite, magnetite, and molybdenite. The biotite randomly or in clusters with minor ferromag- flakes are partly altered to penninite, a variety of nesian minerals and crosscutting muscovite chlorite showing distinctive blue interference laths. Determination of the normative miner- colour. Chemical analysis of the Trout Lake alogy from major oxide chemical analysis of intrusion yields 28% normative quartz, 68 % a typical sample of the granite yields 27% combined feldspar and 4% ferromagnesian min- quartz, 69% feldspar and 4% ferromagnesian erals (Table 1, no.2), which is essentially the minerals (Table 1, no.1) same as the Galena Bay granite. The main phase of the Trout Lake intrusion A notable feature of some of these intru- is a granitic microporphyry. The rock is charac- sions, relates to the occurrence of sulphides - i.e.

198 British Columbia Geological Survey Branch pyritiferous alaskite at the core of the Battle the ‘Selkirk allochthon’, is comprised of dark Range and disseminated molybdenite through- carbonaceous phyllites, grey siliceous schists, out the Trout Lake intrusion. This is in contrast greenschists assigned to the Lardeau Group and to the Kuskanax batholith which contains no a green rusty-weathering schistose altered erup- known mineralization, except for the occasional tive rocks (Jowett Formation?). These rocks grains of pyrite, a feature that seems to explain generally have a southeasterly strike, dip north- why the host rocks intruded by this batholith easterly 50° to 80° and are cut by a series of have provided meager evidence of ore deposi- joints dipping from 40° to 80° northwesterly tion (Cairnes, 1929). (Figure 3). North of Camborne the formations are main- ly metasedimentary rocks represented by phyl- Structural Geology lites, talcose schists, calc-schists and quartzites The Columbia River fault zone is a 250- interbanded with green chloritic schist and rusty kilometre long, linear detachment structure weathering schistose eruptives. These rocks are exposed along the Columbia River extending folded forming a series of tight but gently south- through Revelstoke and southward beyond east plunging, asymmetrical anticlinal and syn- Nakusp on North Arrow Lake (Figure 2). The clinal structures (Figure 4). The folds are Columbia River fault trends subparallel to the inclined to varying degree, to the southwest and Slocan Lake fault and appears to be an offset or northeast, along the mid section of the an en echelon northwest continuation of this Incomappleux River. According to Colpron et al. structure. Both faults dip gently to the east and (1998) the diverse fold inclinations are part of separate major tectonic elements. The footwall the Selkirk fan structure that was developed plate on both faults comprises the ductilely regionally outboard of a pre-Cambrian basement deformed gneissic rocks of the Monashee - ramp during the Columbian orogeny, from mid- Shuswap complex. The hanging wall plate in the Jurassic to Cretaceous. Beaton area, known as the ‘Selkirk allochthon’, At Boyd Creek, the Lardeau shear zone is composed of several tectonic slices compris- marks the boundary between the of the Lardeau ing parts of the Lardeau, Milford and Hamill Group and the older Badshot and Hamill mio- groups and associated intrusions (Read and geoclinal strata in the east part of the map-area. Brown, 1981). The Lardeau Group was deformed prior to mid- The Columbia River fault is a ductile-brittle Mississippian time as shown by the basal con- break that records a history of movement extend- glomerate in the Milford Formation which con- ing from the Mesozoic to Eocene. According to tains foliated clasts of the underlying Broadview Read and Brown (1981), early deformation unit of the Lardeau. Regional constraints indi- resulted in a mylonitic zone up to one kilometre cate probable Devonian - Mississippian timing wide within which the rocks later recrystallized of the orogeny (Antler-age tectonism) and juxta- to the greenschist grade of regional metamor- position of the Lardeau Group against the phism. The fault truncates the major folds and Badshot and Hamill strata along the Lardeau metamorphic zones that had developed in the fault at this time. Further deformation middle Jurassic. Orientation of slickensides and (Columbian) produced large isoclinal folds with strain features in the mylonite shows normal dip subhorizontal axes (Photo 2), and southeast slip displacements with slices of hanging wall (orogen-parallel) stretching lineations. This moving eastward. Late displacement in the deformation was not synchronous everywhere Eocene, manifested by intense fracturing, folding and may have continued through late Jurassic of mylonite and the development of gouge zones, time northeast of Trout Lake. This was followed again shows dip-slip motion with the hanging by Cretaceous dextral strike-slip and normal wall moving eastward. As a result, the tectonic movement on the Lardeau shear zone and other slices east of the Columbia River fault were parallel faults. While apparently the locus of transported tens of kilometres eastward over the several episodes of faulting, the Lardeau shear gneissic complexes. zone does not record the accretion of far-trav- Between the head of Upper Arrow Lake at elled tectonic fragments. Clearly, the sedimento- Beaton and Camborne, the largest tectonic slice, logical evidence ties the Lardeau Group to the

Geological Fieldwork 1998, Paper 1999-1 199 NW DIP SE 0O 90O 0O 000O

N=210 TIEAZIMUTH STRIKE

090O

180O 0O 90O 0O NE DIP SW Fracture Frequency Fracture Attitudes very frequent 140OO - 80 NE frequent 120OO - 45 SW infrequent 040OO - 80 NW few

Figure 3. Fracture frequency plot, main belt, Lardeau Group. Photo 2. Isoclinally folded limestone, Index Formation, Lardeau Group. North American craton (Smith and Gehrels, N 1987). The lack of penetrative fabric distinguishes plutonic rocks of the Kuskanax batholith from Cross Jointing the gneisses and schists of the surrounding areas. OO (040 -80 NW) Fabrics in the shear zone associated with the Columbia River fault indicate easterly down dip

Major Limb displacement of the upper plate. (140OO -80 NE) Geochronological data suggest that some ductile strain exhibited in the gneisses and faulting is early Tertiary age and superimposed on consid- Fold Axis erably older deformation structures possibly (137OO pl l3 SE) related to the original emplacement of the Kuskanax and Nelson batholiths. Minor Limb Carr et al. (1987) believe that uplift in the (120OO -45 SW) early Tertiary resulted in detachment along the Contours of axial linears Slocan and Columbia River faults and Monashee S decollement causing downward movement of the overlying slab to the east. This listric process was Figure 4. Stereographic projection of (lower hemi- accompanied by the development of a system of sphere) of fracture and fold elements, main belt, steeply dipping cross fractures (normal faults) in Lardeau Group. the hanging wall due to extension. The combined fracturing at this time provided convenient chan- nelways and repositories for mineralizing solu- tions (Beaudoin et al., 1991; Church, 1998).

200 British Columbia Geological Survey Branch MINERAL DEPOSITS ty and much surface work together with more than 490 metres of lineal underground devel- The Lardeau and Slocan sections of the opment was completed by Imperial Kootenay Arc are among the regions in British Development Syndicate Ltd. At the end of Columbia where small scale mining has mine operations in 1908 development com- remained viable for many years because of the prised 945 metres of drifting on seven levels, richness of the ores. The Beaton - Camborne 610 metres of crosscuts, 115 metres of raises camp, near the northern extremity of the and 23 metres of shaft sinking. Kootenay Arc, includes 86 mineral deposits of The Eva mine explores and develops two which 18 are past mineral producers having a veins (‘A’ and ‘B’) lying in and along two combined production of more than 60 million fault planes connected by numerous cross grams of silver and significant amounts of gold, veins and stringers. The direction of the veins lead and zinc (Table 2). is about 135°, cutting the steeply dipping host Comprehensive descriptions of the mineral rocks at a low angle. On the No. 6 level the deposits are provided by Brock (1904), Emmens confining faults are 53 metres apart and dip (1915) and Walker et al. (1929), and Linnen et al away from each other. Since the veins follow (1995). The history of many of the various prop- these faults and converge upward, they are erties is also recorded in numerous assessment only 27 metres apart on the No. 2 level (150 reports and the British Columbia Minister of metres above). Mines Annual Reports covering the area. The country rocks are spotted phyllite cut The following property descriptions are by yellow-weathering schistose diabase. The based on MINFILE reports and visits to the prin- veins are quartz accompanied by siderite and a cipal mines by the author during the summer of small amount of pyrite, galena and sphalerite 1998. and some free gold (Photo 3). The veins vary in width from a few centimetres to several metres. Gouge along the faults has evidently Meridian (MINFILE 082KNW064, 066, 065, confined the ore-bearing solution within these 063, 143) planes and the crushed country rock between The Meridian property consists of a consol- them. idation of the Eva, Criterion-Oyster, Cholla, The Criterion-Oyster claim group (MIN- Lucky Jack and Red Horse claim groups. The FILE 082KNW065) adjoins the Eva on the property is situated on the southwest slopes of southeast (Lat 50°47.6’, Long 117°37.6’). In Lexington Mountain, northeast of Camborne addition to a number of surface cuts on these near the confluence of Pool Creek and the claims, a total of 780 metres of underground Incomappleux River. The original access to the development work has been done mostly on two property was via a horse trail following the cable levels following the Criterion vein. This vein is tram line beginning at a log bridge crossing the sub-parallel and appears to converge with the canyon of Pool Creek at Camborne. Later a ‘A’ vein of the Eva mine. The ore was transport- switchback road was constructed to the Eva ed from the mine to the mill by a 1,066-metre- workings from flats of the Incomappleux River long aerial tram - the mill at Camborne was directly below the mine. The road, trail and mine operated by water power taken from Pool Creek working are presently overgrown and in total below the intake of the Eva flume. disrepair. The Criterion vein is a well defined and per- The first discovery of gold in the district sistent structure that strikes 120° and dips 70° was on the Eva claim (MINFILE northeast. No. 1 level develops the vein 30 082KNW066). In 1900 an inexperienced metres below its surface outcrop following a prospector searching for silver-lead ores continuous ore-shoot 300 metres long, averaging found what is now known as the Eva lode 1.5 metres wide, from which about 12,700 (Lat. 50°47.8’, Long. 117°37.8’). Assays tonnes of ore was extracted. The vein is the returned high gold values and a staking rush result of fissure filling with quartz and replace- followed. By 1902 a group of 21 claims was ment of the brecciated country rock consisting of assembled forming the nucleus of the proper- carbonaceous phyllite. In places the vein is solid

Geological Fieldwork 1998, Paper 1999-1 201 1976 1917 1984 1963 1918 1899 1941 1929 1930 1989 1907 1973 1947 1933 1917 1908 Last First 1902 1901 1899 1963 1911 1958 1899 1899 1903 1929 1930 1903 1905 1973 1947 1933 1917 1904 1899 1989 Tungsten: 203 Tungsten: Other Tungsten: 203 Antimony: 4261 Antimony: Antimony: 4261 Antimony: Cadmium: 60371 Cadmium: Cadmium: 60371 Cadmium: 1997 31 23 657 1887 1699 1351 1263 1952 1009 10894 31 22 855 195 2728 1358 8045 1098 3104 1378 9435 23167 114703 182930 31 31 31 62 558 124 249 2333 50830 543899 62 373 778 2302 9860 13499 19408 19315 40434 135019 377839 165499 124215 483652 3097421 1832369 8 5 5 2 6 1 26 74 12 76 24 462 473 618 4347 88763 128063 53480800 370531 10844750 11519402 85348 Table 2. Mineral production in the Beaton-Camborne Camp 2. Mineral Table Spider (L.15752) Spider Lucky Boy (L.5423) Lucky Boy (L.4584) Chief Copper (L.4586) Beatrice (L.4571) Mohawk Ethel (L.4581) Elmo St. Meridian Teddy Glacier Lead Star (L.5654) Goldfinch Mammoth (L.6473) Mike Dollar Silver Gillman Queen Silver Lucky Jack Number (tonnes) (grams) (kilograms) Year Year MINFILE Name Mined Silver Gold Lead Zinc Copper Totals 222965 59802845 968679 11193799 11540168 87345 082KNW003 082KNW004 082KNW040 082KNW041 082KNW045 082KNW059 082KNW062 082KNW064 082KNW069 082KNW071 082KNW076 082KNW077 082KNW097 082KNW101 082KNW127 082KNW150 082KNW187

202 British Columbia Geological Survey Branch Eva was encountered. The No. 2 adit, 53 metres below the upper level, was driven 137 metres to intersect the Criterion vein, however, the contin- uation of the ore-shoot, mined out on the No. 1 level, was not encountered. The Oyster vein outcrops 90 metres north of the Criterion. It strikes 145°, dips 65° northeast and extends onto the Lucky Jack property to the southeast. The only development on the vein is a series of trenches. The Cholla claim group (MINFILE 082KNW143) on Lexington Mountain adjoins the west margin of the Eva and Criterion-Oyster groups (Lat. 50°47.6’, Long. 117°38.0’) and extends beyond Pool Creek to Camborne. The quartz veins on these claims are all gold bearing, however, there is little development other than two short adits, 38 metres apart, driven on the Cholla vein. The Cholla is a well defined verti- cal, north-trending quartz vein cutting phyllites that strike 110° and dip 85° northerly. A sample of a 1.5-metre wide section of the vein from the face of the upper adit assayed 18.5 grams per tonne gold and 13.7 grams per tonne silver. A manganese enriched, pyritic sample from the same general area assayed 41 grams per tonne gold and trace silver. A metre-wide channel sam- ple across the vein in the lower adit, which con- tained many fragments of phyllite in the quartz, assayed 14 grams per tonne gold. (Emmens, 1915, page K256). The Red Horse claim (MINFILE Photo 3. Pyrite, sphalerite, galena and chalcopyrite in vein quartz, ore feed, Meridian mill, Camborne (solid 082KNW063) is situated on Pool Creek 2.4 kilo- circle = 1 cm.) metres upstream from Camborne (Lat. 50°47.0’, Long. 117°36.9’). The principal vein consists quartz but elsewhere it is comprised of a mass of mostly of quartz and has been traced for a dis- reticulating quartz veinlets with phyllite tance of 60 metres up the mountain side by a between. It has been suggested that the carbon in series of open cuts, trenches and an adit. The host the phyllite has acted as a precipitating agent for rock is phyllite striking 135°, dipping vertically. the gold contained in the mineral-bearing solu- The most prominent joint set strikes 045° and tions - the highest grade of gold occurring dips 80° northwesterly; a weaker set dips 15° around the carbonaceous inclusions. northwesterly. At the adit, the vein strikes 155°, The Criterion vein is cut by a mineralized dips 70° northeast and is divided by a median fault striking 043° known as the ‘galena vein’. seam of phyllite into a 2.4 metre wide footwall Where it cuts the Criterion it narrows from more section and a 1.8 metre wide hangingwall sec- than 1 to 0.3 metre wide, retaining well defined tion. Mineralization consists of discontinuous gouge seams along slickensided walls. This seams of massive and disseminated pyrite in the younger vein has been explored for 106 metres quartz. Sampling across the hanging wall section by drifting on the No. 1 level to a point where it assayed trace gold and 20.5 grams per tonne sil- is finally cut off by a shallow south-dipping east- ver. Sampling of the foot wall section assayed 0.7 west fault. At 160 metres into the tunnel a 2.4- gram per tonne gold, and 82 grams per tonne sil- metre wide quartz vein similar to the ‘A’ vein at ver (Emmens, 1915, page K258).

Geological Fieldwork 1998, Paper 1999-1 203 Lucky Jack (L. 8715); (MINFILE 082KNW187) showings. Access to the property is from Camborne via a switchback logging road that The Lucky Jack property is situated on ascends the ridge between Scott Creek and Lexington Mountain and adjoins the Criterion- Menhinick Creek. Oyster and Cholla claim groups on the southeast The property extends 1.5 kilometres follow- (Lat. 50°47.5’, Long. 117°37.1’). There are sev- ing a series of gold-bearing quartz veins that eral veins on this property that have been strike southeast coincident with the regional prospected but the only significant development structural trend. The claims were staked at the is confined to surface cuts and shallow under- turn of the century and operated for several years ground workings which test the continuation of by Northwestern Development Syndicate. The the 200 metre long Oyster vein. The vein ranges chief work was on the Goldfinch and adjoining from 1 to 4.6 metres wide and consists mostly of Dorothy and Independence claims. Early reports quartz with bands of carbonaceous phyllite min- mention numerous trenches and adits and a eralized with pyrite. The vein has an average tramline connecting the Goldfinch mine with the strike of 145° and a dip of 54° northeast. Close to mill at the mouth of Menhinick Creek. the line of the Sleve Namon and Mascotte claims The Goldfinch claim was the focus of the the vein has been opened by a large cut from initial development work. In 1903 production of which ore was mined and processed in a small 726 tonnes of ore yielded 16.2 kilograms of gold two-stamp mill from 1904 to 1908. A crosscut and 4.98 kilograms of silver and, in 1904, an driven through ore on the floor of the cut exposed additional 590 tonnes returned 4.67 kilograms of a wide section of the vein. It dips 35° northeast gold and 633 grams of silver. Much of this pro- and is divided into three bands by narrow seams duction was from an open cut. The vein system of graphitic schist. Sampling and assay results is explored by two principal adits and a shaft. A across 1.5 metres on the hanging wall section short upper adit (Photo 4) was driven northeast yielded 6.9 grams per tonne gold, and 33 grams to intercept a splayed vein striking 135° and dip- per tonne silver. Results from 1.8 metres of the ping variably 20°-40° southwest and 75° north- central section assayed 10.3 grams per tonne gold east. The vein is 10 to 30 centimetres wide, and and 17.1 grams per tonne silver; while 0.9 metre contains quartz, accessory pyrite, galena and vis- across the footwall section assayed 28 grams per ible free gold. Assays on selected samples range tonne gold and 33 grams per tonne silver. About up to 62 grams per tonne gold and 21 grams per 38 metres southeast of this old cut, and 30 metres tonne silver (Emmens, 1915, page 251). The below it, a crosscut was driven into the hill to the lower adit, located 20 metres below the upper vein and a drift extended for 12 metres to the adit, explores the area mostly west and south of northwest. Near this point, a sample of the 0.8 the upper workings. A strong quartz vein at the metre hanging wall section of the vein assayed shaft, dipping 80° southwest, is aligned with a 16.1 grams per tonne gold; the middle section similar vein striking 155° at the lower portal, across 0.85 metre returned 0.3 gram per tonne located 130 metres to the southeast of the shaft. gold; and the footwall section across 1.7 metres Assay results for several one metre sections returned 6.5 grams per tonne gold (Emmens, taken across the shaft vein range up to 0.68 1915, pages K257). grams per tonne gold and 5.83 grams per tonne silver (Read, 1981). There are two principal quartz veins on the Goldfinch (L. 5654); (MINFILE 082KNW076) Independence claim. These are hosted in phyllite The Goldfinch property, comprising the and occur in, and adjacent to, a rusty-weathered Goldfinch (L.5654), Walrus (L.5653), Dorothy diabase dike. The No. 1 vein was originally (L.12481), Independence (L.12460) and 11 addi- exposed by trenching which follow the bedding tional Crown granted claims and fractions, is planes for 120 metres striking 135°, dipping 60° centered on the west side of the Incomappleux to 70° northeast. An assay sample taken across River, 3.7 kilometres north-northwest of 0.9 metre of the vein returned 2.1 grams per Camborne (Lat. 50°49.4’, Long. 117°39.5’). tonne gold and 3.4 grams per tonne silver. The Elevations on the property range from 488 No. 2 vein has been opened and drifted on from metres at river level to 1,040 metres at the main a short adit. This vein strikes 155° and dips 70°

204 British Columbia Geological Survey Branch southwest. A splay of this vein, sampled across 4.9 metres, assayed 17.1 grams per tonne gold and 10.2 grams per tonne silver (Emmens, 1915, page 250). After a long period of dormancy Eaton Mining and Exploration Co. Ltd. renewed exploration in 1971 and shipped ore in 1979. The property was then acquired by Windflower Mining Ltd. in 1985. Granges Exploration Ltd., in an option agreement with Windflower, completed additional work on the Dorothy zone which led to further production in 1989. The Dorothy zone consists of a number of quartz lenses and pods on what appears to be an axial plane shear. This mineralized structure trends southeast for a several hundred metres from the Dorothy claim, across the western extremity of Goldfinch to the boundary of the Walrus claim. The main Dorthy structure has been tested by drilling to a depth of 99 metres and traced on strike for 546 metres. Width of the structure ranges between 1.8 and 9.1 metres. The East Zone, locat- ed 20 metres east and parallel to the Dorothy zone, is comprised of en echelon quartz veining contain- ing visible gold and a minor amount of galena, sphalerite and a trace of chalcopyrite. The zone Photo 4. Main portal, Goldfinch mine, Menhinick has a strike length of 150 metres, depth of 80 Creek area. metres and width of 1.98 metres. The West zone, traced by drilling for 60 metres along strike, is a drill holes, is 180,000 tonnes grading 10 grams sulphide-rich lens containing coarse pyrite with per tonne gold (Northern Miner, March 1987). native gold in quartz within graphitic phyllite, similar to the Dorothy zone. The Dorothy North is Spider (L. 15752); (MINFILE 082KNW045, 80 metres in length and separate from the main 044, 048, 049) zone. Best assay results returned 11.65 grams per tonne gold over 3.61 metres (George Cross The Spider mine (also known as the Sunshine Newsletter, # 224, 1987). Lardeau mine) is on the south side of Pool Creek, A soil sampling program in 1988 by 2.7 kilometres by steep road southeast of Granges revealed a number of geochemical Camborne (Lat. 50°46.8’, Long. 117°36.5’). The anomalies. Follow up prospecting resulted in the Spider (L.15752), Spider No.1 (L.15753), Eclipse discovery of a new gold bearing quartz-carbon- (L.5170) and Sandy (L.8719) are the nucleus of a ate vein near Scott Creek. The Scott Creek zone group of Crown granted claims and fractions that is located 500 metres north of the Dorothy zone extends from the valley of Pool Creek southeast- and comprises quartz stockwork and quartz-car- erly towards Mohawk Creek. bonate veining averaging three to four metres The first discovery of ore in this area was and occasionally 10 metres in width. Assay made in 1910 on the Spider claim. Development results on grab and chip samples reportedly work continued until 1949 during which there range from 3 to 27 grams per tonne gold were small intermittent shipments of hand-sort- (Northern Miner, Aug. 10, 1987). ed ore (Photo 5). Sunshine Lardeau Mines Ltd. Estimated ore reserves for the combined acquired the property and initiated a diamond largest zones on the property reported by drilling program which discovered Nos. 4 and 5 Granges Exploration Ltd., based on 60 diamond veins in 1950. A crosscut was driven to the veins

Geological Fieldwork 1998, Paper 1999-1 205 on No. 5 level and No. 6 adit was extended to intersect No.4 vein. A mill was installed in the old Meridian building on Pool Creek in May 1952. Concentrates were transported by truck to Beaton and thence by the Arrow Lakes barge to the rail-head at Nakusp and from there to smelters in the United States. Berens River Mines Ltd. provided additional funding to gain control of operations. In 1953 the No. 10 adit was driven. In 1956 the company was liquidated and operations passed to Newmont Mining Corp. Mining and milling operations were sus- pended on May 14, 1958. The mine is underlain by southeasterly strik- ing, steeply dipping volcanic and sedimentary rocks of the Lardeau Group. Sedimentary rocks of the Broadview Formation include medium grey to greenish quartzites, greywackes, car- bonaceous phyllites and quartz sericite schist. The volcanic rocks of the Jowett Formation comprise massive fragmental lenses and lava flows, some chlorite schist and a few thin beds of banded iron formation. In the fragmental units, extreme elongation of the clasts, caused by synkinematic metamorphism, has imparted a crude secondary layering subparallel to the pri- Photo 5. Ore bin, No. 8 Adit, Spider mine, Pool mary stratification. Creek area. The volcanic rocks are host to most of the ore. At the Spider mine the volcanic rocks faults. The faults, spaced at ~ 275-metre intervals, underlie a lens-shaped area roughly 2,300 cut across the bedding at about 50°, showing some metres long by a maximum of 600 metres wide. dextral strike slip displacement. From northwest As a unit, the volcanics are considerably more to southeast the veins are named the Sandy competent than the sedimentary rocks. The few (MINFILE 082KNW048), Barclay (MINFILE schist zones that are found are generally only a 082KNW049), No. 4 (MINFILE 082KNW045) few feet wide and are believed to represent strike and Eclipse (MINFILE 082KNW044). or bedding parallel faults. Past development at the Spider mine consists of The major structures have been inferred at least seven levels. Production by the end of 1957 from cleavage parasitic relationships in the vol- was mainly from one ore shoot on the No. 4 vein. canic and sedimentary rocks and the attitude of This vein, striking 170°, dipping 75° east, was the minor folds. Large folds with many drag developed from surface to a depth of 200 metres. folds appear to be confined to the central part of Ore grade material was intersected in drilling an the volcanic belt. In general the folds are tight additional depth of 70 metres below this level. isoclinal. The axes of all the folds strike north- The Eclipse vein (Lat. 50°46.6’, Long. westerly, and the axial planes are inclined 117°36.3’), accessible via the No. 10 adit level steeply to the northeast. The folds plunge to the of the Spider mine, produced 31,748 tonnes of southeast at angles averaging from 25° to 30°. ore in the period 1956-58. This development A northwesterly trending fault, known local- exposed the top of the ore body (005°/75° east) ly as the Camborne fault, cuts the north limb of through a vertical range of 46 metres. a southeasterly plunging anticlinal structure The principal showing on the Sandy claim along the north side of Pool Creek. (Lat. 50°46.9’, Long. 117°37.1’) is a quartz vein The orebodies occupy four main veins on a which strikes 160°. It is crosscut by four subpar- system of steeply dipping, northerly trending allel faults. The ore minerals occur as irregular

206 British Columbia Geological Survey Branch veinlets and small pockets along these faults. A tonnes of copper, 10,845 tonnes of lead and small ore shoot discovered in this setting was 11,519 tonnes of zinc from 128,063 tonnes of explored but the limited tonnage indicated did ore (MINFILE, also see Keys, 1956). not warrant production. Measured geological reserves at the Spider The Barclay vein is hosted by altered green- mine are 25,398 tonnes grading 4.4 grams per stone and exposed at the east end of a road cut. tonne gold, 255 grams per tonne silver, 6.19 per The vein consists of galena sparingly dissemi- cent lead and 6.34 per cent zinc (George Cross nated in quartz. Diamond drill programs in 1954 News Letter, April 26, 1987). and 1956 failed to locate any extension of this mineralization. There is no record of ore produc- Beatrice (L. 4586); (MINFILE 082KNW040) tion from this zone. The orebodies range from 30 metres to 120 The Beatrice mine (Photo 6) is situated, at metres in length and from 0.45 to 4.5 metres in 2,103 metres elevation, near timber line, at the width. They are essentially tabular with some head of the southeast fork of Mohawk Creek pinching and swelling. Tensional branch veins (Lat 50°44.3’, Long 117°33.5’). The property are fairly common. Some of these are more than consists of six contiguous claims including the 30 metres long and 100 metres deep - most of Beatrice (L.4586) and Folsom (L.4587). Access these pinch out within a metre of the main vein. to the property is via the badly eroded and over- The main constituents of the ore bodies are grown Spider mine road, 11 kilometres southeast quartz, pyrite, sphalerite and galena and minor of Camborne. Construction of a new logging amounts of ankerite, chalcopyrite, and rarely road to Mohawk Creek has begun from a point arsenopyrite and tetrahedrite. Sections com- just southwest of the canyon section on the posed essentially of pyrite, sphalerite and galena Incomappleux River road, about five kilometres are common. The order of deposition of the vein northeast of Beaton. minerals is ankerite, quartz, pyrite, sphalerite, The Beatrice and Folsom claims were staked chalcopyrite, galena. Fine and coarse grained in 1897 and Crown granted about 1902. They varieties of galena are present. were originally part of the Beatrice Group locat- Zones of carbonate alteration and oxidation, ed on the southwest spur of Mount Pool.. The as much as several metres wide, occur along the original discovery by two prospectors consisted faults principally on the eastern or hangingwall of a small chimney of clean galena at the contact side with or without accompanying vein miner- of schist and crushed slate. A 10-metre shaft was alization. These zones comprise altered rem- sunk on the ore, which was further developed by nants of the volcanic country rock, ankerite, dis- a 60-metre adit, known as the No. 1 level. The connected quartz stringers and a small amount of No. 2 level was driven from the opposite side of chrome mica. In the oxidized zone, most of the a shoulder (jutting north from the main ridge) to pyrite, sphalerite and gangue has been leached, a vertical depth of 46 metres below the No. 1 leaving a mixture of clay, limonite and galena. level. In 1898 approximately 200 tonnes of sil- The No. 4 orebody shows vertical oxidation for ver-rich ore was hand mined. 40 metres below the surface. The property was worked continuously from In summary, the main ore controls are a 1898 to 1906. In 1902 the Beatrice Mines Ltd. series of northerly trending fissures (splays or was organized. The company resumed opera- tension fractures?) that appear to be related to tions in 1910, but ceased work in 1911. In 1918 the through-going southeasterly trending the property was bonded to New Era Mines Ltd. Camborne fault along the valley of Pool Creek. and operations continued through 1920. At this Hydrothermal solutions were controlled by the point the workings consisted of a several hun- intersection of the principal fissures with fold dred metres of drifts, crosscuts and raises on crests. Mineralization appears to have favoured three levels. In 1921, a two-bucket tramway was the Jowett Formation because of the volcanic installed to connect the No. 2 adit with ore bins composition and the competent, fissure-sustain- on the main trail. However, the high zinc content ing characteristics of these rocks. of the ore prevented satisfactory market arrange- Total production to the end of 1958 was 370 ments at the time and this discouraged further kilograms of gold, 53,480 kilograms of silver, 85 work. In 1954 a private company, Beatrice

Geological Fieldwork 1998, Paper 1999-1 207 Photo 6. Panoramic view of the Beatrice camp site looking northeast from portal. Mines Ltd., rehabilitated the mine and during the The Beatrice is on the same belt of Lardeau next few years rebuilt the road. In 1964 the prop- metasedimentary rocks as the Silver Cup (MIN- erty was optioned to Dakota Silver Mines Ltd. FILE 082KNW027), Nettie L (MINFILE During this and the following years, limited 082KNW100) and True Fissure (MINFILE work was carried out but the property and equip- 082KNW030) mines of the Ferguson camp to ment was eventually abandoned. the southeast.

208 British Columbia Geological Survey Branch Black slates, carbonaceous schists, grey and 1,832 kilograms of silver, 182,930 kilograms of reddish-brown weathering grits and quartzites lead and 10,894 kilograms of zinc (MINFILE). and greenish grey talcose schists underlie the property. On average the rocks strike 140° and Mammoth (L.6473); (MINFILE 082FNW077) dip 65° northeast. Ore occurs as irregular veins in shear zones, The Mammoth property comprises four on bedding plane slips and crosscutting faults. Crown granted claims situated between 2,070 and The veins range from a few centimetres to a few 2,530 metres elevation, straddling the narrow metres wide and consist of sphalerite, galena, northwest ridge extending from the summit of tetrahedrite and pyrite in quartz gangue with Mount Goldsmith (Lat. 50°51.4’, Long. minor calcite. Replacement is considered to be 117°34.5’). The original route to this remote an important factor in the formation of the ore. mountain top property was by steep mountain The mine workings develop two principal trail from the Incomappleux River valley, howev- vein-lodes - the Beatrice and the Main veins. er, the only practical access nowadays is by heli- The Beatrice vein, which was the original dis- copter, 9.7 kilometres northeast of Camborne. covery at surface, strikes 050° and dips 65° The property was worked from 1904 to 1907 southeast across the axis of the controlling syn- by the Edward Baillie Syndicate of Nelson B.C. clinal structure. The Main vein, found only on Production amounted to 76 tonnes of hand sort- the lower levels of the mine, strikes 140° and ed ore that yielded 249 grams of gold, 484 kilo- dips 65° northeast. grams of silver, 23 tonnes of lead and 1.95 The No. 1 adit was crosscut to the Beatrice tonnes of zinc (MINFILE). vein where considerable stoping was done. The mine consists of an adit driven 180 Above the level the vein was mined for a verti- metres southeast and several side tunnels cross- cal distance of about 18 metres and horizontally cutting the main ridge. Some tunnels broke for 20 metres. The ore appears to have been hand through to surface which now give views of the cobbed in the stope and backfilled with rejected valleys of Boyd Creek to the east and the subgrade debris. The mineralization consists of a Incomappleux River to the northwest (Photo 7). solid band of pinching and swelling massive sul- These workings develop a seam of galena, pyrite phides, ranging up to 50 centimetres wide. The and argentiferous tetrahedrite, up to 25 centime- hanging wall is a two metre wide siliceous zone tres thick, on an essentially horizontal rolling carrying disseminated sulphides. Sampling at fissure, dipping locally 5° to 10° northeast, in a the face of No. 1 level across 0.6 metre yielded fine grained, dark grey limestone bed that strikes an assay result of 0.3 grams per tonne gold, 450 150°, and dips 80° northeast. These beds are suc- grams per tonne silver, 5.2 per cent lead and 7.8 ceeded to the southwest by other units of the per cent zinc (Ashton, 1977). Index Formation (Lardeau Group), including a The Main vein on the No. 2 level consists of bed of pure white crystalline limestone and west solid bands of sulphides and disseminations up to of that a thick band of green chlorite schist. The three metres wide, in a graphitic shear zone. In the host rocks at the mine site are cut by a set of most easterly workings of the intermediate level, northeast striking vertical joints. Southeast from the ore zone follows a parallel partly mineralized the adit, along the ridge, there are several small structure trending 138°, dipping 60° northeast. quartz veins and a band of limestone that has A third vein, known as the ‘Gold Lode’ has been heavily replaced by pyrite (with minor been traced for a few hundred metres in open gold) and iron carbonates. cuts below the main road. This vein, contains pyrite and a sprinkling of galena. It is 1.2 to 1.8 Lucky Boy (L. 5423); (MINFILE metres wide and strikes 155° and dips steeply to 082KNW003, 004) the northeast. Assay results returned 5.1 grams per tonne gold and 32.5 grams per tonne silver The Lucky Boy property consists of a small (Emmens, 1915, page K267). group of Crown granted claims of which the Altogether, 618 tonnes of hand sorted ore Lucky Boy (L.5423), Horseshoe (L.5342) and was shipped from the property, mostly between Copper Chief (L.4584) (MINFILE 1899 and 1917, yielding 558 grams of gold, 082KNW004) are the most important. The prop-

Geological Fieldwork 1998, Paper 1999-1 209 Photo 7. Main portal area, Mammoth mine, Mount Goldsmith. erty is located on the northern shoulder of Trout shaft on three levels. The underground workings Mountain overlooking Wilkie Creek (Lat. on the Horseshoe claim are accessible by two 50°38.5’, Long. 117°36.2’). Access to the prop- shafts collared 46 and 59 metres due west, erty is by dirt road, five kilometres from the respectively, from the Luck Boy shaft. Both of north end of Trout Lake. these shafts were driven as declines down dip The first claims in the area, the Lucky Boy about 50 metres on the extension of the Lucky and Copper Chief, were staked in 1897 and 1901, Boy vein. The Copper Chief workings lie respectively. The property was worked originally approximately 1.2 kilometres southwest from for high-grade silver-lead ore. From 1901 to 1906 the main Lucky Boy and Horseshoe shafts (Lat. a total of 395 tonnes of this type of sorted ore was 50°38.0’, Long. 117°36.5’). The main showing, shipped and from 1911 to 1917 an additional 25 at the elevation of 1,575 metres, is exposed in an tonnes of similar ore was mined and shipped to adit driven at 027° on a steeply dipping fault. smelters. In 1942 a further 20 tonnes of tungsten The geology of the area has been described (scheelite) ore was hand sorted and shipped. In by Read and Brown (1981). The area in the vicin- 1972 an additional 24 tonnes silver-lead-zinc ore ity of Wilke Creek on Trout Mountain is under- was shipped. Total recovery from the claims was lain by schists, pelitic quartzites, calcareous phyl- 3,232 kilograms of silver, 117,431 kilograms of lites and limestone beds of the Lardeau Group lead and minor copper, zinc and gold. that underwent regional metamorphism and mul- The ore was developed by a number of sur- tiple episodes of deformation. The strike of beds face cuts, adits and inclined shafts - most of the across the claims is rather uniform at 150°. work was on the Lucky Boy claim and some of Bedding within the quartzite is obscured, but it the remainder on the adjacent Horseshoe claim. and most limestone or skarn contacts dip from The principal workings are accessible from an 65° to very steeply northeast. In several places inclined shaft that extends downward southeast- small dragfolds plunge 20° to 30° northwest. This erly for 58 metres on the Lucky Boy claim. kind of folding, combined with gentle northwest- Drifts were developed east and west from this erly plunging fold axes, seems typical of the area.

210 British Columbia Geological Survey Branch There are two types of mineral deposits on No. 1 level. At 17 metres from the shaft, scheel- the property. One is typical of the main Lucky ite mineralization is present in the remaining Boy and Copper Chief ore deposits and consists pillars and exposed along the drift westward. In of nearly flat, drusy quartz veins which cut the vein, in the stoping face at 30 metres from steeply dipping quartzites and limestones of the the shaft, there is an attractive display of scheel- Lardeau group at nearly right angles. These ite across 0.7 metre that contains an estimated veins carry galena, sphalerite, pyrite, tetra- 1.84% tungsten oxide (J.S. Stevenson, 1942, hedrite, minor native silver and scheelite in a unpublished notes). quartz gangue. The second type is skarn miner- There is no development below the No. 3 alization in silicified limestone. The skarns con- level of the Lucky Boy mine. At that depth the tain garnet, pyroxene, pyrrhotite and consider- vein fissure appears to cut a limestone bed but able scheelite but little or no galena, tetrahedrite without significant accompanying mineraliza- and only small amounts of sphalerite. They are tion. On the lowest level, the vein as exposed is rarely more than several metres in length and narrow and contains little sulphides. However, vary from 1 to 12 metres in width. The skarns scheelite mineralization extends nine metres up usually crop out over exceedingly rugged and from the base of the shaft, and seven metres east steep mountain sides. on both walls of the drift - the drift having been The Lucky Boy vein has an easterly strike, driven 40 metres east and west from the shaft with an average dip of 50° south that becomes accessing raises that go through to the No. 2 almost horizontal in places. The vein apparently level. follows the major jointing of the enclosing sili- The distribution of scheelite mineralization cified schist and quartzite. The sulphides reticu- indicates the existence of a shoot of several hun- late through the vein quartz, sometimes occur- dred tonnes of ore that rakes southeastward from ring as almond-shaped masses. The following the Horseshoe workings at surface, beginning by order of formation of the metallic minerals is the east shaft, traversing through to the raise at suggested - galena, tetrahedrite, chalcopyrite the west end of No. 2 level and to the base of the and pyrite, galena, sphalerite. Galena is found shaft on No. 3 level, coinciding with the main both in and surrounding tetrahedrite; sphalerite shoot of sulphide mineralization which was pre- encloses both. Chalcopyrite encloses and forms viously mined. A grab sample of this scheelite veins in the foregoing assemblage, and pyrite ore assayed 1.41% tungsten oxide and 0.63% and galena form the matrix for the other sul- phosphorous (Stevenson, 1943, page 133). phides. From the way chalcopyrite embays the There appears to have been a considerable tetrahedrite, it looks as if it was formed at the tonnage of scheelite ore in place before the sil- expense of the latter - perhaps the result of a ver-lead quartz-sulphide vein was mined. reaction of tetrahedrite with pyrite. Unfortunately, the sulphides and scheelite were From the shaft on the No. 1 level (100-foot in the same sections of the vein and, as a result level) drifts have been driven to connect with the of the original focus on precious metals, only the Horseshoe workings and stopes opened at inter- high grade silver-lead ore was mined and much vals along the strike of the vein. Near the face of of the scheelite was discarded. The bulk of this the west drift, a ribbon of ore 15 centimetres rejected material was used as fill in empty stopes wide, containing abundant tetrahedrite, assayed or in surface waste dumps. 5 grams per tonne gold, 6,500 grams per tonne Other less mineralized veins can be found silver and 3.3% copper. Also, a sample across a on parallel fissures. Locally, there is evidence of 25 centimetre width of the vein, at the head of replacement of inclusions of country rock where the stope, assayed 13.7 grams per tonne gold, the veins widen. 2,600 grams per tonne silver and 47.2% lead Skarn occurrences are principally southeast (Emmens, 1915, page K 317). of Wilkie Creek. A total of 16 skarns have been The No. 2 level is driven eastward and found between elevation 1,090 metres (150 westward from the shaft. To the east, the drift- metres above the creek) and the crest of the ing was carried 75 metres without encountering northeast spur of Trout Mountain, at 1,630 significant ore. To the west, the vein was fol- metres elevation. The skarn mineralization con- lowed 37 metres and stoped throughout to the sists of varying amounts of pyrrhotite and fine

Geological Fieldwork 1998, Paper 1999-1 211 grained scheelite. The skarn occurrences appear high grade ore to the Trail smelter. Mining con- to coincide with three limestone beds or perhaps tinued intermittently until 1918 resulting in a a single limestone bed that was intricately folded. total production of 74 tonnes of ore yielding 378 Several skarns lie on the southwest side of a kilograms of silver and 8,045 kilograms of lead. steep gully extending from the Copper Chief adit Underground development of the vein system at 1,475 metres elevation down to creek level. extends over a vertical range of 50 metres and The lowest showing is about 150 metres below consists of one crosscut adit and seven drift adits the old low trail that leads southwest from the - the longest of which is 90 metres. Since that Lucky Boy camp along the side of Wilkie Creek. time there has been no mining activity and the The skarn is light coloured and composed main- Crown granted claims have revered. In the sum- ly of calcite with small amounts of garnet and mer of 1965, the ground was restaked by diopside. It occurs on the northeast side and Rexony Mining Co. Ltd., and a road was built close to the top of a band of grey limestone that connecting the property to an existing logging extends uphill from the creek. The skarn is about road. The workings were mapped and sampled 2.4 metres wide and is moderately well mineral- and in June 1966 three holes were drilled that ized with scheelite. The skarn is below an anti- totalled 236 metres. In 1978 Cominco Ltd. clinal fold in quartzite that plunges 20° north- staked the surrounding area and conducted west. detailed geochemical surveys, from 1979 to Additional skarn exposures are located in 1981, across the surrounding terrain. the gully at 1,408 metres elevation on the high Subsequently there has been no additional devel- trail from the Lucky Boy camp to the Copper opment. Chief adit. One exposure of dark coloured skarn The showings at the Ethel mine are a series in this area is 3.3 metres wide and contains some of closely spaced quartz veins hosted in dark scheelite and abundant pyrrhotite. Another dark grey phyllites and limestones of the Lardeau coloured skarn band, exposed on the southwest Group. A layer of fine grained limestone 15 to 23 side of the gully, is 16 metres wide and contains metres thick contains the principal vein-lodes, a high proportion of diopside and epidote. however, some veins extend beyond the lime- Scheelite is disseminated through this skarn stone into the phyllite. The veins strike 130° to across four metres adjacent to a narrow enclo- 155° and dip 60° northeast essentially parallel to sure of grey limestone. At the portal of the the schistosity of the phyllites. The quartz, con- Copper Chief adit, the skarn is 0.6 to 1.2 metres taining scattered grains of galena, sphalerite, wide and encloses several lenses of limestone. A pyrite and tetrahedrite form lenses up to 46 cen- sample across 1.2 metres of the skarn and lime- timetres thick following the schistosity. They stone assayed 1.06% tungsten oxide (Holland, have mostly been mined out, but judging from 1952, page A186). surface exposures and small underground stopes, they formed en echelon bodies with an average dip of 40° to the northeast. The old Ethel (MINFILE 082KNW059) workings passed from one lens to the next, giv- The Ethel mine is situated northeast of the ing the appearance of a single continuous vein summit of Trout Mountain, between 1,800 and (Photo 8). Selected samples from the surface, 1,900 metres elevation, overlooking Humphries containing sulphides or showing copper stain, Creek (Lat. 50°37.2’, Long. 117°34.9’). It is assay as much as 2,800 grams per tonne silver reached by a switchback logging road that con- (Fyles, 1966, page 230). nects the property to the settlement of Trout Lake, four kilometres to the northeast. The Ethel group, comprising the Ethel, Teddy Glacier (MINFILE 082KNW069) Esther, May-Day, Frances and Noel claims, was The Teddy Glacier property is located at 2200 located in 1898 on a silver-lead rich vein lode. In metres elevation on Mount McKinnon, at the head 1902 the property was purchased by a of a tributary of Stephany Creek, 16 kilometres Philadelphia based company and, after lying idle north of Beaton (Lat. 50°52.1’, Long. 117°44.8’). for four years, the mine was worked on a small Access is 30 kilometres by road from Beaton via the scale resulting in a shipment of 480 sacks of main Incomappleux River and Sable Creek roads.

212 British Columbia Geological Survey Branch The property was staked in 1924 by G. cutting was done in the upper adit. In 1935, a Ritchie and G. Edge. High grade float strewn for lower adit, begun 55 metres below the upper adit, 300 metres downslope led these prospectors to was driven 18 metres then abandoned because the the mineral occurrences at the foot of the reced- upper level results were not encouraging. ing ‘Teddy’ glacier. The claims were allowed to lapse in 1942. Teddy Glacier Mines, Ltd. was incorporated The central claims of the group, covering the in 1924 by Blockberger and Associates to acquire main showings, were then restaked in 1942 by the important Rambler-Cariboo, Blackhead, A.D. Oakley who subsequently sold controlling Margaret and Mary Jane claims. A trail was interest to A.M. Richmond representing opened to the property in 1925, and in late 1926 a American Lead-Silver Mines Ltd. Richmond did crosscut adit was begun just below the main show- a detailed re-evaluation of the property. The ing. The adit was advanced to the vein during property was optioned to Columbia Metals 1927 and then work stopped. In 1929 the Bush and Corporation Ltd. in 1952. However, no activity McCulloch interests provided funds for extending other than road building was report and the the crosscut to a second vein. A shipment of five option was abandoned. tonnes of ore was made at this time yielding 2,302 In 1959 the property was acquired under grams of silver, 124 grams of gold, 855 kilograms joint ownership by Sunshine Lardeau Mines of lead and 1,351 kilograms of zinc. Ltd., Maralgo Mines Ltd. and Magnum No further activity was reported until a syndi- Consolidated Mining Co. Ltd. - an indirect inter- cate, financed by Mines Selection Trust of est was secured by Transcontinental Resources London, began extensive development work in Ltd. Work by this consortium during 1963 1934. A considerable amount of money was spend included geological mapping, sampling of the on equipment, trails and camp buildings. Also, at underground workings and 150 metres of dia- this time, about 500 metres of drifting and cross- mond drilling in six holes. Road construction in 1964 disclosed new showings on the Bell No. 14 claim, located 900 metres southeast of the main workings. However, a drill program (which totalled 660 metres of diamond drilling) was somewhat discouraging and did not establish the continuity of the ore zones. The Teddy Glacier property is underlain by tightly folded and sheared limestones, carbona- ceous phyllites and grits of the Index Formation, Lardeau Group. These rocks trend southeast (115°-135°), dip 50°-60° northeast and are cut by steeply dipping cross-joints. The ore zones are confined to quartz veins that vary from a few centimetres to 1.2 metres in width, are up to 40 metres long and occupy two adjacent fractures, striking 163° and 170°, and dipping steep easterly. On surface and in the upper adit level, these fractures join to form the ‘Big Showing’. This showing comprises a large body of quartz roughly nine metres long carrying bodies of coarse sulphides up to 1.5 metres wide. Assay results across 4.9 metres at the widest point on the vein yielded 8.9 grams per tonne gold, 280 grams per tonne silver, 12.9% lead and 7.1% zinc (Richmond, 1949). Other showings occur 90 metres to the northwest (‘Dunbar vein’) Photo 8. Adit development, Ethel mine, Humphries and again at 180 and 300 metres on the same Creek area. structure. Assay results on the Dunbar vein

Geological Fieldwork 1998, Paper 1999-1 213 across 0.7 metres returned 6.9 grams per tonne the east side of the dike contains small irregular gold, 840 grams per tonne silver, 34.0% lead and masses of serpentinite and barite plus irregular 2.8% zinc (Richmond, 1949). galena replacements. The sulphides occur as masses and bunches of almost clean (70-80%) galena, pyrite, spha- Trout Lake (MINFILE 082KNW087) lerite and minor chalcopyrite in quartz gangue and, less frequently, as intimately intermixed fine The Trout Lake deposit is located 60 kilo- grained sulphides in narrow lenses in quartz. metres southeast of Revelstoke on the northern Tetrahedrite occurs as small inclusions in the spur of Trout Mountain between 1450 to 1520 galena. In most of the ore, silver is closely asso- metres elevation (Lat. 50°38.2’, Long. ciated with galena and gold with pyrite (~29 117°36.2’). Access to the property is by logging grams of gold per tonne of pyrite). The wall road, five kilometres west of the north end of rocks on both the foot and hanging wall sides of Trout Lake. the orebodies are hard, competent limy-quartzitic The first claims in the area, the Lucky Boy sedimentary rocks that have been silicified, frac- and Copper Chief, were staked in 1897 and tured and faulted during folding, and to a minor 1901, respectively. A total of 414 tonnes of extent after sulphide mineralization. hand-sorted ore was shipped from several small The probable and inferred ore reserves at the veins from the Lucky Boy between 1901 and Teddy Glacier mine are 44,212 tonnes of ore 1917 - from which 2,898 kg of silver and 121 grading 161.1 grams per tonne silver, 4.4 grams tonnes of lead were recovered; a further 18 per tonne gold, 7.9 per cent lead and 6.8 per cent tonnes of tungsten (scheelite) ore was shipped in zinc (Sunshine Lardeau Mines, Ltd., 1964 1942. Annual Report). Molybdenite was first reported in 1917, but it was not until 1969 that a subsidiary of Scurry Rainbow Oil Ltd. carried out trenching and a Great Western (L.4503); (MINFILE diamond drill program. The property was 082FNW213) optioned by Newmont Exploration of Canada in The Great Western property, comprising the 1975. From 1976 to 1982, a joint venture project Great Western, June, Silver Tip and All Blue by Newmont and Esso Minerals Canada Ltd. claims, is located two kilometres north of delineated the deposit by surface drilling and Whiskey Point on the shore of the Northeast subsequently by diamond drilling and bulk sam- Arm of Upper Arrow Lake (Lat. 50°43.4’, Long. pling from an exploration adit (Photo 9). 117°49.3’). The claims extend from lake level, at Underground development on the property con- 425 metres elevation, to 900 metres elevation on sists of about two kilometres of crosscuts and the southeast slopes of Mount Sproat. The prop- drifts. The pipe-like stockwork deposit extends erty is reached from the shoreline of Arrow Lake from the surface to a depth greater than 1000 and short access roads. metres and contains estimated reserves of 49 The rocks underlying the claim group are million tonnes grading 0.19% MoS2 (Linnen et undivided units of the Lardeau Group consisting al., 1995). The property has been inactive since of grey to white crystalline limestone, green 1982 and is now wholly owned by Newmont chloritic schist and a granodiorite body. The Mines Ltd. Lardeau rocks strike southeast at 120° on aver- The geology of the area has been described age. The large granodiorite body is generally by Holland (1952, 1953), Boyle and Leitch concordant with these beds. The lowest showing (1983) and Linnen et al. (1995). The property is located at 60 metres above the lake consists of a centred on the Trout Lake stock, a small granitic width of 3.5 metres of quartz in granodiorite. intrusion, in a belt of highly deformed metased- Galena and pyrite occur sparingly along the frac- imentary rocks of the Lardeau Group (Lower tures and as disseminations in both the quartz Paleozoic). vein and the dike. At 210 metres above the lake, The Lardeau Group is bowed around the at the face of a short adit, mineralization occurs eastern margin of the Kuskanax batholith. The across a width of 2.4 metres. Higher above the group consists of argillite, quartzites, carbonate lake, at 440 metres, white and grey marble on beds and schists that underwent middle Jurassic

214 British Columbia Geological Survey Branch regional metamorphism and deformation. Light grey to black argillite beds are interlayered with very fine grained grey to tan phyllites and brown biotite-chlorite-sericite schists with prominent segregated quartz layers and lenses. The carbon- ate beds are composed of massive and banded grey to white limestone and dolomite with vari- able skarn development. The skarnified rocks contain quartz, calcite, epidote, diopside, garnet, prehnite, phlogopite and minor amounts of idocrase, wollastonite, sphene and actinolite. The Trout Lake stock is late Cretaceous age (76 Ma) and consists of four intrusive phases, the earliest of which is porphyritic granodiorite, comprising the bulk of the stock. This is fol- Photo 9. View of main portal, Trout Lake prospect. lowed by aplite dikes and a succession of some- what younger dikes including porphyritic quartz phic assemblage in the phyllites and schists, diorite, granodiorite, and quartz diorite. These consisting of muscovite- chlorite- tremolite-cli- dikes cut off and are cut by mineralized quartz nozoisite- plagioclase- potassium feldspar- and veins. quartz, suggests a temperature of roughly The porphyritic granodiorite is a grey, medi- 400°C. um grey rock characterized by euhedral quartz Hydrothermal alteration at the Trout Lake eyes (10%) set in a seriate-textured groundmass deposit comprises; a central quartz- orthoclase- of euhedral plagioclase (35%), anhedral quartz albite- (biotite)- ‘potassic zone’, coincident with (35%), potassium feldspar (10%), and altered molybdenum mineralization and overlapped by biotite relics. a slightly later antipathetic quartz-sericite-pyrite The young porphyritic quartz diorite is ‘phyllic zone’. The youngest alteration is quartz- medium to dark grey with a peppery appearance muscovite- ankerite- pyrite- (microcline). This caused by fine biotite flakes in the groundmass. alteration is developed pervasively along faults These rocks are composed of quartz (35%), pla- or as halos around late subhorizontal quartz gioclase phenocrysts (45%), potassium feldspar veins. Late chlorite and pyrite filled fractures are (< 5%) and accessory biotite. The quartz diorite widespread but never pervasive. In detail many is also distinguished by hornblende phenocrysts local variations and some retrograde effects are and late magmatic potassium feldspar porphy- observed. The relationships of biotite, sericite roblasts. and chlorite are complex due to the presence of The aplite dikes, commonly less than a regional metamorphic sericite, chlorite and metre thick, are gradational to pegmatitic quartz- biotite; the later development of hornfels biotite potassium feldspar veins. around the contacts of the stock; and the super- The regional metamorphic grade increases imposed hydrothermal sericite and biotite relat- towards the southwest on the property, with ed to vein margins. chlorite, biotite and finally garnet and oligoclase Molybdenite mineralization is best devel- appearing in the phyllite and schist facies of the oped in a quartz vein stockwork around the mar- Lardeau Group, as the Kuskanax batholith is gin of the Trout Lake intrusion and dike off- approached. Superimposed on this regional shoots of the same body. Molybdenite occurs as metamorphic gradient is a thermal biotite horn- fine to medium grained flakes and rosettes fels surrounding the Trout Lake stock. This con- accompanied by pyrite and pyrrhotite, mainly tact metamorphic aureole, measuring 1.2 x 2 along the margins of the veins (Photo 10). In the kilometres, was developed during emplacement highest grade zones, molybdenite is strongly dis- of the stock. The aureole is easily recognized in seminated on microfractures in areas of intense the calcareous lithologies where the appearance quartz vein flooding, some areas measuring as of clinozoisite defines the outermost isograd. At much as 200 metres long and 20 metres wide. surface, the highest grade of contact metamor- Molybdenite grades drop off markedly towards

Geological Fieldwork 1998, Paper 1999-1 215 the centre of the large granodiorite mass and replacements in limestone along faults adjacent wherever the younger quartz diorite dikes are to the Trout Lake stock. The tungsten occurs as encountered. scheelite, with pyrrhotite and minor chalcopyrite Veins in the Trout Lake stockwork comprise on the Copper Chief (MINFILE 082KNW004) several sets. The older veins trend southeast par- and as scheelite in quartz veins with galena, allel to the major fold axes and most of the faults sphalerite and tetrahedrite on the Lucky Boy (135°, subvertical). Secondary vein sets occur (MINFILE 082KNW003). on cross-joints striking 045° and dipping sub- Skarns, manifested mainly by clinopyroxene vertical; and there are late subhorizontal veins. and garnet, and hosting minor scheelite, occur as In addition, conjugate subvertical, shear-related replacements of marble along faults adjacent to veins, striking 005° and 095°, are prominent. the Trout Lake stock. Tremolite ± clinozoisite The close spatial and temporal relationship (calc-silicate alteration) locally replaces between these veins and the Trout Lake stock clinopyroxene and in turn is replaced by biotite suggests that hydraulic fracturing followed and/or calcite, indicating that skarn predated emplacement of magma. Furthermore, this sug- potassic (biotite) alteration. gests that the fracturing was caused either by the release of orthomagmatic fluids, or by hot over- DISCUSSION pressured metamorphic or meteoric fluids. Post mineral faults observed in drill core cut The most striking feature about the ore off good grade molybdenite, but displacements, deposits in the Beaton-Camborne camp is that seen underground are clearly only minor read- they occur in well defined linear mineral belts justments between fault blocks. Only the ‘Z’ trending southeast parallel to the regional strike fault, which bounds the deposit on the east, of the formations (Brock, 1904). These are appears to have significant dip-slip movement. referred to as the ‘central’, ‘northeast’ and Tungsten mineralization is restricted to lens- ‘southwest’ belts. The central belt consists of an es of garnet-clinopyroxene skarn occurring as alignment of properties that extends southeaster-

Photo 10. Molybdenite-bearing quartz stringer in granite porphyry, Trout Lake prospect (solid circle = 1 cm).

216 British Columbia Geological Survey Branch ly from Scott and Menhinick Creek across the three principal attitudes based on 210 measure- valley of the Incomappleux River near ments (Figure 3). These are (1) 140°/80°NE and Camborne to the southwest slopes of Lexington (2) 120°/45°SW and (3) 040°/80°NW. Fracture Mountain and to Pool and Mohawk creeks. If set (1) is the principal layering, foliation and fis- extended further to the southeast, the trend sility of the sedimentary and volcanic rocks of aligns with the main mineral belt in the Ferguson the area; (2) is like (1) but a subsidiary fabric area containing the Nettie, Triune and Silver (short limb) in assymetrical folds; (3) is the main Cup mines. The northeast mineral belt is less cross joint direction. These fractures are mostly well defined and extends more or less along the steeply inclined relative to the Columbia River divide between Lexington and Boyd Creeks and fault and underlying Monashee gneiss complex across the head of Pool Creek into the Ferguson that form the footwall of the Selkirk allochthon. area. The southwest belt consists of a few Sets (1) and (2) are also the main fracture and aligned deposits on the slopes of Trout vein direction (dipping mostly to the northeast) Mountain, southwest of Trout Lake. at the Meridian, Goldfinch, Ethel and Beatrice mines (Table 3). Cross joints (3) trend northeast- erly subparallel to some of the veins at the Trout Control and Style of Mineralization Lake and Meridian mines. The belts are clearly controlled by regional The southwest mineral belt is dominated by structures and the physical characteristics of the the Trout Lake molybdenum porphyry - tungsten deformed rocks. For example the central belt skarn system. The deposit is temporally and spa- follows the axis of the Silvercup anticline and tially related to the emplacement of a small, late the trend of the Cup Creek fault from the Cretaceous granodiorite intrusion. Molybdenite Ferguson camp (Fyles and Eastwood, 1962). It occurs in a quartz vein stockwork and as dis- appears that the favourable zones of mineraliza- seminations in the granodiorite and, to some tion along this belts developed at sites of intense extent, in the metasedimentary host rocks. In fracturing where the fault approaches the crest of general molybdenite appears to accompany an anticline - local structures having formed sub- alkali feldspars, but in detail it is intimately sequent to the folding. To the northeast the min- associated with incipient muscovite replacing eral deposits are scattered and the beds in which albite and potassium feldspar. Fluorite and barite the deposits are found comprise relatively are uncommon in this system. incompetent limestone units which were isocli- Tungsten mineralization is found in skarn nally folded, sheared and deformed again. lenses in limestone bands peripheral to the main Silver-lead-zinc ores are typical of the cen- molybdenum zone. Scheelite occurs with tral belt and occurrences to the northeast. The pyrrhotite and minor chalcopyrite at the Copper ore minerals are mainly pyrite, galena, sphalerite Chief prospect and scheelite in quartz veins with and smaller amounts of chalcopyrite and galena, sphalerite and tetrahedrite at the Lucky pyrrhotite. Silver is the most important com- Boy mine. modity and it occurs in argentiferous tetra- Veins associated with the Trout Lake deposit hedrite, galena and less commonly as native sil- are diverse and complicated (Linnen et al., ver and sometimes in argentite, polybasite, ruby 1995). At least five orientations are recognized. silver, stephanite and electrum. Gold is present The oldest veins are subvertical and strike south- in small quantities and is rarely seen as native easterly parallel to the regional foliation (135°), gold or electrum. Quartz is the dominant gangue similar to (1) and (2) above. Orthogonal to this mineral, but carbonates such as ankerite, calcite are steeply dipping veins striking 045°, similar and/or dolomite are significant gangue compo- to (3) and late subhorizontal veins. A conjugate nents in some veins. The deposits are character- set of subvertical shear related veins at 005° and ized by open-space fillings with limited wall 095° is also found. Although there is a close spa- rock replacement. In a few places where replace- tial and temporal relationships between the veins ment is important, carbonate gangue is relative- and the Trout Lake stock, no radial or concentric ly abundant. pattern occurs such as usually associated with The fracture frequency pattern in the central hypabyssal intrusions. This suggests a moderate- belt, underlain by the Lardeau Group, shows ly deep intrusion regime where hydraulic frac-

Geological Fieldwork 1998, Paper 1999-1 217 Table 3. Principal vein attitudes at mines and mineral prospects.

Occurrences Location Vein Attitudes (MINFILE No.) Lat. Long. Lucky Boy (003) 50º 38.5' 117º 36.2' 100º/25ºSW Copper Chief (004) 50º 38.0' 117º 36.5' 150º/80ºNE Beatrice (040) 50º 44.3' 117º 33.5' 138º/60ºNE 155º/80ºNE 050º/65ºSE 140º/65ºNE Mohaw k (041) 50º 46.7' 117º 35.8' 155º/72ºNE 120º/80ºNE 160º/80ºNE 090º/60ºNE Excise (043) 50º 46.5' 117º 36.1' 155º/80ºNE Eclipse (044) 50º 46.6' 117º 36.3' 005º/75ºE Spider (045) 50º 46.8' 117º 36.5' 170º/75ºE St. Joe (046) 50º 47.3' 117º 36.9' 135º/90º Sandy (048) 50º 46.9' 117º 37.1' 165º/90º Ethel (059) 50º 37.2' 117º 34.9' 130º/60ºNE Red Horse (063) 50º 47.0' 117º 36.9' 155º/70ºNE Meridian (064) 50º 47.4' 117º 37.2' 120º/70ºNE 043º/90º Oyster (065) 50º 47.6' 117º 37.6' 146º/65ºNE Eva (066) 50º 47.8' 117º 37.8' 135º/80ºNE 135º/80ºSW Teddy Glacier (069) 50º 52.1' 117º 44.8' 163º/80ºNE 170º/80ºNE Lead Star (071) 50º 51.8' 117º 41.1' 145º/50ºNE Burniere (072) 50º 51.2' 117º 41.7' 125º/80ºSW Goldfinch (076) 50º 49.4' 117º 39.5' 152º/80ºSW 135º/20ºSW Mammoth (077) 50º 51.4' 117º 34.5' 135º/10ºNE Big Show ing (078) 50º 52.7' 117º 34.9' 035º/50ºSE Trout Lake (087) 50º 38.2' 117º 36.2' 135º/90º 045º/90º Silver Dollar (101) 50º 44.7' 117º 33.9' 155º/60ºNE Gillman (127) 50º 44.9' 117º 34.1' 165º/35ºNE Agnes (132) 50º 51.8' 117º 42.5' 035º/45ºSE Nelson (138) 50º 49.6' 117º 41.0' 120º/50ºSW Cholla (143) 50º 47.6' 117º 38.0' 180º/90º Lucky Jack (187) 50º 47.5' 117º 37.1' 145º/54ºNE turing within the existing structural framework, the Monashee gneissic core complexes along the caused by the release of orthomagmatic fluids Columbia River and Slocan Lake faults. The (perhaps combined with metamorphic and mete- Trout Lake intrusion dated 76 Ma (Boyle and oric solutions), coincided with the emplacement Leitch, 1983) and associated Mo and W deposits of the magma. Linnen and William-Jones (1987) represent the beginning, and the Ag, Pb, Zn have interpreted the magmatization and the veins, such as found at the Enterprise mine in the development of the orthogonal fracture system Slocan City area, dated 58.2 ± 0.7 Ma (Beaudoin to be the result of release of elastic stresses dur- et al., 1992), represent the culmination of the ing the late Cretaceous / early Tertiary uplift of mineralizing cycle. the Kootenay arc. Source of Mineralization Age of Mineralization The solutions that formed ore deposits ascend- The age of mineralization in the Beaton- ed along whatever channels that were available in Camborne camp coincides with a major late the host rocks such as bedding planes, shear zones Cretaceous through early Tertiary tectonic tran- and cross fractures (Walker et al., 1929). In the sition (to 59 Ma) that is marked by uplift, Beaton-Camborne camp predominant fissures are decollement and intrusion in the Kootenay Arc. approximately parallel to the strike of the forma- This was followed by extensional exhumation of tions, and because the schistocity with few excep-

218 British Columbia Geological Survey Branch SW Mineralized Fissures NE Paleotopography Lardeau Shear

C R F

MD

modified from: Colpron, et al. (1998)

Late Cretaceous granite Hamill Group Purcell Supergroup, ?

Lardeau Group Windermere Supergroup Proterozoic basement gneisses

MineralizationCRF Columbia River Fault MD Monashee Detachment Figure 5. Schematic cross-section of the Selkirk fan structure, during late Cretaceous to early Tertiary time, showing mineralizing systems controlled by doubly verging assymetrical and isoclinal folds and trusts above Dogtooth crustal ramp. tions also parallels the strike, it is clear that the Zn vein deposits in the Slocan area during solutions were forced to ascend along definite Eocene extension related to the Slocan fault. zones subparallel to bedding. Consequently, the ore This is similar to the model proposed (this study) deposits for the most part are aligned more or less for the Camborne area. Figure 5 shows the ore along the strike of the beds. fluids tapped from magmatic and metamorphic A cross-section through the Selkirk sources, including the high grade gneisses of the allochthon shows a fan-like arrangement of underlying Monashee Complex. southwesterly and northeasterly-verging tight folds with steeply dipping axial planes (Figure CONCLUSIONS 5). These structures formed as a result of thrust- ramping of the covering beds along the The veins of the Beaton-Camborne camp are Monashee decollement from mid-Jurassic to hosted by the Lardeau Group and consist mostly early Tertiary (Colpron et al., 1998). It is these of galena, sphalerite and pyrite in quartz and car- structures that are also believed to have provid- bonate gangue. Molybdenite and scheelite are ed the main plumbing system and the regional associated with the Trout Lake intrusion. control of mineralization. Early workers regarded the granitic rocks as The source of mineralizing solutions was the singular magmatic - hydrothermal source of believed by early workers to be the Kuskanax the mineralization, however, recent studies sug- batholith. However, the deposits in the area are gest a more complicated genesis. The veins are much younger and mostly remote from the near- fracture fillings and replacements that appear to est Kuskanax body. In the case of the southwest be related to the Columbia River fault and belt, which is closest to the Kuskanax, there is Monashee decollement that forms the footwall clear evidence that the late Cretaceous Trout of the Selkirk allochthon. Prolonged movement Lake intrusion is the source of the Mo-porphyry, on this fault system during the late Creataceous W-vein and skarn deposits. and early Tertiary is believed to have sustained The origin of the numerous Ag-Pb-Zn-Au channelways for mineralizing solutions, which deposits of the central and northeast belts is are the result of commingling of metamorphic more complicated. Holk and Taylor (1997) sup- and magmatic fluids and meteoric water. port the general proposal of Beaudoin et al. (1992) that ascending metal-bearing aqueous ACKNOWLEDGMENTS fluids, derived from crystallizing granitic magma, mixed with deeply circulation meteoric The writers are obliged to David Lefebure of ground waters. This produced numerous Ag-Pb- the Geological Survey Branch for suggesting the

Geological Fieldwork 1998, Paper 1999-1 219 project, to Jim Logan for scientific improve- Church, B.N. (1998): Metallogeny of the Solcan City ments to this report, and Trygve Höy for his Mining Camp (082F11/14); in Geological advice in the field. Thanks are also owing to Jody Fieldwork 1997, B.C. Ministry of Employment and Spence for his field assistance and Mike Fournier Investment, Paper 1998-1, pages 22-1 to 22-13. and Verna Vilkos of the Branch for their techni- Crosby, P. (1968): Tectonic, plutonic and metamor- cal advice, and to David Lefebure and Dorthe phic history of the central Kootenay Arc, Jakobsen for their technical editing duties. British Columbia; Geological Society of America, Special paper 99. REFERENCES Eastwood, G.E.P. (1957): Spider, Eclipse etc. Armstrong, R.L. (1988): Mesozoic and Early (Sunshine Lardeau Mines Ltd.); in Minister of Cenozoic magmatic evolution of the Canadian Mines Annual Report 1956, B.C. Ministry of Cordillera; Geological Society of America, Energy, Mines and Petroleum Resources, pages Special Paper 218, pages 55-91. 99-105. Ashton, A.S. (1977): Beatrice Property near Emmens, N.W. (1915): Lardeau Mining Division; in Camborne; Unpublished private report, Arch Minister of Mines Annual Report 1914, B.C. Mining and Milling Ltd., 13 pages. Ministry of Energy, Mines and Petroleum Resources, pages K245-K283. Beaudoin, G., Taylor, B.E. and Sangster, D.F. (1991): Silver-lead-zinc veins, metamorphic core com- Emmens, N.W. (1934): Report on the Meridian Mine, plexes and hydrologic regimes during crustal Camborne, British Columbia; Unpublished pri- extension; Geology, Volume 19, pages 1217- vate company report, 33 pages. 1220. Fyles, J.T. (1966): Ethel; in Minister of Mines Annual Beaudoin, G., Taylor, B.E. and Sangster, D.F. (1992): Report 1966, B.C. Ministry of Energy, Mines Silver-lead-zinc veins and crustal hydrology and Petroleum Resources, page 230. during Eocene extension, southeastern British Fyles, J.T. (1967): Geology of the Ainsworth-Kaslo Columbia, Canada; Geochemica et Area, British Columbia; B.C. Department of Cosmochemica Acta, Volume 6, pages 175- Mines and Petroleum Resources, Bulletin 53, 196. 125 pages. Boyle, H.C. and Leitch, C.H.B. (1983): Geology of Fyles, J.T. and Eastwood, G.E.P. (1962): Geology of the Trout Lake molybdenum deposit, B.C.; the Ferguson area, Lardeau district, British Canadian Institute of Mining and Metallurgy, Columbia; B.C. Department of Mines, Bulletin Bulletin 76, Number 849, pages 115-124. 45, 92 pages. Brock, R.W. (1904): The Lardeau District, B.C.; Gehrels, G.E. and Smith, M.T. (1987): “Antler” Geological Survey of Canada, Summary allochthon in the Kootenay Arc?; Geology, Report, part A, pages 42A-81A. Volume 16, pages 769-770. Cairnes, C.E. (1929): Geological reconnaissance in Holk, G.J. and Taylor, H.P. (1997): 18O/16O homog- the Slocan and Upper Arrow Lakes area, enization of the middle crust during anatexis: Kootenay District, British Columbia; Thor-Odin metamorphic core complex, British Geological Survey of Canada; Summary Columbia; Geology, Volume 25, pages 31-34. Report 1928, part A, pages 94A-108A. Holland, S.S. (1952): Lucky Boy and Copper Chief Carr, S.D., Parrish, R.R. and Brown, R.L. (1987): (Major Exploration Ltd.); in Minister of Mines Eocene structural development of the Valhalla Annual Report 1952, B.C. Ministry of Energy, complex, southeastern British Columbia; Mines and Petroleum Resources, pages 183-187. Tectonics, Volume 16, pages 175-196. Holland, S.S. (1953): Lucky Boy and Copper Chief Colpron, M., Warren, M.J. and Price, R.A (1998): (major Explorations Ltd.); in Minister of Mines Selkirk fan structure, southeastern Canadian Annual Report 1953, B.C. Ministry of Energy, Cordillera -Tectonic wedging against an inherited Mines and Petroleum Resources, pages 144-145. basement ramp; Geological Society of America, Bulletin, Volume 110, No.8, pages 1060-1074.

220 British Columbia Geological Survey Branch Höy, T. and Dunne, K.P.E. (1997): Early Jurassic Read, P.B. (1976): Lardeau map area (82K west half), Rossland Group, southern British Columbia, British Columbia; Geological Survey of Part 1 - stratigraphy and tectonics; B.C. Canada, Paper 76-1A, pages 95-96. Ministry of Employment and Investment, Read, P.B. and Brown, R.L. (1981): Columbia River Bulletin 102, 124 pages. fault zone - southeastern margin of the Klepacki, D.W. and Wheeler, J.O. (1985): Shuswap and Monashee complexes, southern Stratigraphy and structural relations of the British Columbia; Canadian Journal of Earth Milford, Kaslo and Slocan groups, Goat Sciences, Volume 18, pages 1127-1145. Range, Lardeau and Nelson map areas, British Read, P.B. and Wheeler, J.O. (1976): Geology and Columbia; in Current Research, part A, Mineral deposits, Lardeau west half (82K); Geological Survey of Canada, Paper 85-1A, Geological Survey of Canada, Open-File 432, pages 277-286. Map 1:125,000. Keys, M.R. (1957): The Geology of the Sunshine Read, W.S. (1981): The 1980 Exploration Program Lardeau Mine; The Canadian Mining and on the Goldfinch Group Mineral Claims for Metallurgical Bulletin, Volume 50, Number Eaton Mining and Exploration Ltd.; B.C. 540, pages 218-221. Ministry of Energy, Mines and Petroleum Leech, G.B., Lowdon, J.A., Stockwell, C.H. and Resources, Assessment Report No. 9137. Wanless, R.K. (1963): Age Determinations and Reesor, J.E. and Moore, J.M. (1971): Petrology and Geological Studies; Geological Survey of Structure of Thor-Odin Gneiss Dome, Shuswap Canada, Paper 63-17, pages 24-25. Metamorphic Complex, British Columbia; Linnen, R.L. and Williams-Jones, A.E. (1987): Geological Survey of Canada, Bulletin 195, Tectonic control of quartz vein orientations at 149 pages. the Trout Lake stockwork molybdenum deposit Reesor, J.E. (1973): Geology of the Lardeau map are, - implications for metallogeny in the Kootenay east half, British Columbia; Geological Survey Arc; Economic Geology, Volume 82, pages of Canada, Memoir 369, 129 pages. 1283-1293. Richmond, A.M. (1949): Report on the Teddy Glacier Linnen, R.L. and Williams-Jones, A.E., (1990): Mining Property of American Lead Silver Evolution of aqueous-carbonic fluids during Mines Ltd., Lardeau Mining Division, B.C.; contact metamorphism, wallrock alteration, unpublished private company report, 12 pages. and molybdenum deposition at Trout Lake, British Columbia; Economic Geology, Volume Sevigny, J.H. and Parrish, R.R. (1993): Age and ori- 85, pages 1840-1856. gin of late Jurassic and Paleocene granitoids, Nelson Batholith, southern British Columbia; Linnen, R.L., Williams-Jones, A.E., Leitch, C.H.B. Canadian Journal of Earth Sciences, Volume and Macauley, T.N. (1995): Molybdenum min- 30, pages 2305-2314. eralization in a fluorine-poor system: The Trout Lake stockwork deposit, southeastern British Smith, M.T. and Gehrels, G.E. (1990): Geology of the Columbia; in Porphyry Deposits of the Lardeau Group east of Trout Lake, British Northwestern Cordillera of North America; Columbia (Silvercup Ridge, Mount Wagner Canadian Institute of Mining and Metallurgy, and Mount Aldridge areas); B.C. Ministry of Special Volume 46, pages 772-780. Energy, Mines and Petroleum Resources, Open File 1990-24. Okulitch, A.V. (1985): Paleozoic plutonism in south- eastern British Columbia; Canadian Journal of Smith, M.T. and Gehrels, G.E. (1991): Detrital zircon Earth Sciences, Volume 22, pages 1409-1424. geochronology of upper Proterozoic to lower Paleozoic continental margin strata of the Parrish, R.R. and Wheeler, J.O. (1983): A U-Pb zir- Kootenay Arc - implications for the early con age from the Kuskanax batholith, south- Paleozoic tectonic development of the eastern eastern British Columbia; Canadian Journal of Canadian Cordillera; Canadian Journal of Earth Sciences, Volume 20, pages 1751-1756. Earth Sciences, Volume 28, pages 1271-1284. Read, P.B. (1973): Petrology and structure of the Smith, M.T. and Gehrels, G.E. (1992): Stratigraphic Poplar Creek map area, British Columbia; comparison of the Lardeau and Covada groups - Geological Survey of Canada, Bulletin 193, implications for revision of stratigraphic rela- 144 pages. tions in the Kootenay Arc; Canadian Journal of Earth Sciences, Volume 29, pages 1320-1329.

Geological Fieldwork 1998, Paper 1999-1 221 Stevenson, J.S. (1943): Tungsten deposits of British Columbia, B.C. Department of Mines, Bulletin 10, pages 130-133. Thompson, R.I. (1978): Geology of the Akolkolex River area; B.C. Ministry of Energy, Mines and Petroleum Resources, Bulletin 60, 77 pages. Walker, J.F., Bancroft, M.F. and Gunning, H.C. (1929): Lardeau map-area, British Columbia; Geological Survey of Canada, Memoir 161, 142 pages. Wheeler, J.O. (1968): Lardeau (west half) map area, British Columbia (82K W1/2); in Report of Activities, part A, Geological Survey of Canada, Paper 68 - 1A, pages 56-58.

222 British Columbia Geological Survey Branch